This invention relates generally to a safety device for a hang glider.
More specifically, this invention relates to an alarm device which warns a pilot of danger if he attempts a take off without being properly hooked in to the glider.
A significant number of hang gliding accidents resulting in fatalities are due to glider pilots taking off from a cliff or other high point without attaching their harnesses to their gliders. In 1983 there were eleven deaths, approximately 20% of all hang glider fatalities that year, due to a failure of the pilot to hook-in to his glider. There were an additional number of serious injuries caused by that same error.
Hang glider pilots, as a group, are well aware of these dangers and have instituted "hang-check" procedures in which at least one other person physically verifies that the pilot is properly attached to the glider. In an additional check, the pilot will put his weight on the harness to assure that he is hooked in. Yet, in spite of these precautions, accidents continue to occur. Pilots may simply forget or ignore established procedures. A pilot may be flying alone and have no one else to perform a hang check. He may perform a hang check and later may unhook to adjust a strap or give another pilot a hang check and then forget to hook back in and have another hang check.
Other than hang check procedures, there is nothing that is observable by the pilot to warn him that he is not properly hooked in and is in danger. As he prepares for take-off, the weight of the glider is on his shoulders and his hook-up strap is slack. The strap is behind him, being attached to his harness in the middle of his back, so he has no visual clue that he is, or is not, hooked in. In a cliff take off, the pilot runs a short distance and literally steps off into space as he and his glider become airborne. This short take-off run does not give time for the pilot to feel the glider begin to lift his weight (or not lift his weight) before he is over the cliff edge. Faced with this situation, most pilots are so surprised that they lose their grip and fall almost immediately. Others manage to hang on for a short time. A lucky, and strong, few have managed to hang on, control their glider, and survive.
Some hang gliders have been equipped with wind direction indicator flags, attached to the nose of the glider with the words "HOOK-IN" printed on the flag. Such reminders may be of some use to the novice but routine written warnings of whatever kind tend to be ignored after a short time. A number of quite specific characteristics would be required for an alarm warning of a failure to hook-in to be effective and yet acceptable to hang glider pilots. It would have to have a low false alarm rate else it would be either removed or disabled. It necessarily would have to be light and of rugged construction and present low wind drag so as to have a negligible effect on glider performance. It should be difficult to "cheat" on and be detectable by others around the hang glider as well as by the pilot. It would desirably be relatively inexpensive, be simple to maintain and operate and be adaptable for use with virtually all of the different varieties of hang gliders. Finally, it should not be offensive to the self image of the hang glider pilot.
It is evident that a warning device meeting the above criteria would be of great potential benefit to the sport of hang gliding.